Compact and high-efficiency device for Raman scattering measurement using optical fibers

Area of Science:

• Optics and Photonics
• Materials Science
• Spectroscopy

Background:

• Operating optical measurement devices within high-power magnets at low temperatures presents significant challenges.
• Confining measurements to small sample regions requires specialized, high-efficiency optical systems.
• Minimizing interference from external factors like magnetic fields and vibrations is crucial for data integrity.

Purpose of the Study:

• To design and develop a compact, high-efficiency optical measurement device for use in confined, extreme environments.
• To enable precise optical measurements of light emitted from small sample areas within high-power magnets at low temperatures.
• To mitigate interference from magnetic fields and mechanical vibrations, and to reduce optical fiber fluorescence.

Main Methods:

• Development of a compact confocal optical system with integrated lens focusing and tilting capabilities.
• Utilization of a piezo-driven translation stage for micron-scale sample positioning and focus control.
• Incorporation of 10 m-long optical fibers to isolate the measurement setup from magnetic field leakage and mechanical vibrations.
• Implementation of a technique to minimize fluorescence signals originating from the optical fibers.

Main Results:

• Successful design and development of a high-efficiency optical measurement device.
• Demonstrated micron-scale focus control for precise sample positioning.
• Effective isolation from magnetic field leakage and mechanical vibrations using long optical fibers.
• Minimization of optical fiber fluorescence achieved.

Conclusions:

• The developed optical measurement device is suitable for operation in challenging high-power magnet, low-temperature environments.
• The device enables high-efficiency light measurement from small sample regions with high signal-to-noise ratios.
• Raman scattering measurements of monolayer graphene confirmed the device's operational effectiveness and high performance.